package com.wc.codeforces.DP.状态机.Kevin_and_Puzzle;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.StringTokenizer;

/**
 * @Author congge
 * @Date 2025/5/5 10:55
 * @description
 * https://codeforces.com/contest/2061/problem/C
 */
public class Main {
    /**
     * 思路：
     * f[i][0] 表示第 i 个人是骗子的个数
     * f[i][1] 表示第 i 个人是诚实的个数
     * 保证两个骗子不站在一起
     * f[i][0] = f[i - 1][1]
     *
     * i - 1 是 真实
     * if (a[i] == a[i - 1]) f[i][1] += f[i - 1][1]
     * i - 1 是 骗子
     * if (a[i] == a[i - 2] + 1) f[i][1] += f[i - 1][0]
     */
    static FastReader sc = new FastReader();
    static PrintWriter out = new PrintWriter(System.out);
    static int N = 200010, P = 998244353;
    static long[][] f = new long[N][2];
    static int[] a = new int[N];
    static int n;

    public static void main(String[] args) {
        int T = sc.nextInt();
        while (T-- > 0) {
            n = sc.nextInt();
            for (int i = 1; i <= n; i++) {
                a[i] = sc.nextInt();
                f[i][0] = f[i][1] = 0;
            }
            if (a[1] == 0) f[1][1] = 1;
            f[1][0] = 1;
            for (int i = 2; i <= n; i++) {
                // i 是骗子
                f[i][0] = f[i - 1][1];

                // i 是真实的

                // i - 1 是骗子
                if (a[i] == a[i - 2] + 1) f[i][1] = (f[i][1] + f[i - 1][0]) % P;
                // i - 1 是真实的
                if (a[i] == a[i - 1]) f[i][1] = (f[i][1] + f[i - 1][1]) % P;
            }
            long res = (f[n][0] + f[n][1]) % P;
            out.println(res);
        }
        out.flush();
    }
}

class FastReader {
    StringTokenizer st;
    BufferedReader br;

    FastReader() {
        br = new BufferedReader(new InputStreamReader(System.in));
    }

    String next() {
        while (st == null || !st.hasMoreElements()) {
            try {
                st = new StringTokenizer(br.readLine());
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return st.nextToken();
    }

    int nextInt() {
        return Integer.parseInt(next());
    }

    String nextLine() {
        String s = "";
        try {
            s = br.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }
        return s;
    }

    long nextLong() {
        return Long.parseLong(next());
    }

    double nextDouble() {
        return Double.parseDouble(next());
    }

    // 是否由下一个
    boolean hasNext() {
        while (st == null || !st.hasMoreTokens()) {
            try {
                String line = br.readLine();
                if (line == null)
                    return false;
                st = new StringTokenizer(line);
            } catch (IOException e) {
                throw new RuntimeException(e);
            }
        }
        return true;
    }
}

